THE  PRODUCTION  OF  ALLOYS  OF 
TUNGSTEN  AND  OF  MOLYB¬ 
DENUM  IN  THE  ELEC-  <3 


TRIC  FURNACE 


•"i 

"5  ^ 


THESIS 

Presented  to  the  Faculty  of  the  Department  of  Philosophy  of  the 
University  of  Pennsylvania  in  partial  fulfillment  of  the 
requirements  for  the  Degree  of  Doctor 
of  Philosophy 


CHARLES  LAWRENCE  SARGENT 

Peace  Dale,  Rhode  Island 


1900 


PHILADELPHIA 
Avil  Printing  Company 


1900 


Return  this  book  on  or  before  the 
Latest  Date  stamped  below.  A 
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11148-S 


INTRODUCTION. 


With  the  introduction  of  the  electric  furnace,  the  new 
field  of  chemistry  at  high  temperatures  was  opened  to  inves¬ 
tigation.  In  the  past  few  years  this  has  [received  much 
attention,  especially  by  Moissan,  who  has  succeeded  in 
reducing  the  most  refractory  oxides,  also  in  volatilizing 
many  of  them  as  well  as  certain  metals  which  had  been 
considered  infusible. 

Moissan  (La  Four  Electrique ,  p.  246)  describes  a  method 
of  preparing  alloys  of  vanadium,  using  the  pentoxide  as 
the  source  of  vanadium. 

Bernoulli  (Pogg.  Annal.  hi,  p.  573)  prepared  alloys  of 
tungsten  with  copper,  lead,  bismuth,  cobalt,  nickel,  etc.  His 
method  of  working  consisted  in  mixing  the  oxides  of  the 
two  metals  with  lampblack,  placing  the  mixture  in  a  cru¬ 
cible  and  then  heating  it  in  an  ordinary  furnace.  Proceeding 
in  this  manner  he  was  not  able  to  obtain  alloys  containing 
rmore  than  10  per  cent  of  tungsten. 

Knowing  the  comparative  ease  with  which  tungsten  and 
molybdenum  are  reduced  from  their  oxides,  it  was  thought 
T-that  it  might  be  possible  to  mix  these  oxides  with  oxides  of 
pother  metals  and  then  reduce  the  mixture  in  the  electric 
furnace,  obtaining  as  a  final  product  an  alloy  of  the  two 
metals. 

In  the  following  experiments  the  furnace  used  was  of  the 
type  known  as  the  “  Moissan.”  The  carbon  for  the  reduc¬ 
tion  was  prepared  by  ignition  of  cane  sugar.  The  cru¬ 
cibles  were  made  of  graphite  modeled  in  the  form  of  an 
assay  scorifier.  This  shape  is  preferable,  as  it  allows  the  arc 
to  play  directly  on  the  bottom  of  the  crucible.  For  some 

(3) 


'157o0 

V 


4 


of  the  experiments  these  crucibles  were  lined  with  magne¬ 
sium  oxide,  thus  preventing  the  hot  metal  from  absorbing 
any  of  the  graphite. 

Unless  otherwise  mentioned  the  graphite  crucibles  were 
used.  After  each  reduction  the  furnace  was  closed  and 
allowed  to  cool  before  removing  the  crucible  containing  the 
fusion. 


PRELIMINARY  EXPERIMENTS. 

Before  taking  up  the  work  of  forming  alloys,  the  follow¬ 
ing  experiments  were  conducted  with  tungstic  acid  ;  the 
object  being  to  obtain  the  best  conditions  for  its  reduction. 

Experiments  /,  If  III. 

io  grams  of  tungsten  trioxide  ....  Voltage,  58-70. 

20  “  “  carbon . Amperage,  55-125. 

Time,  7  minutes. 

The  product  was  a  black  granular  mass,  but  it  contained 
no  tungsten.  This  was  probably  due  to  the  large  excess  of 
carbon. 


Experiment  IV 

3  grams  of  tungsten  trioxide  .....  Voltage,  65. 

3  “  “  carbon . Amperage,  150. 


Time,  2  minutes. 

Obtained  as  the  product,  a  metallic  button  containing 
88.45  per  cent  of  tungsten. 

Method  of  Analysis. 

The  metal  was  mixed  with  sodium  carbonate  and  potas¬ 
sium  nitrate  and  fused.  The  fusion  was  taken  up  with  water, 
then  acidified  with  nitric  acid,  evaporated  to  dryness,  heated 


to  about  1750  C.,  a  small  amount  of  nitric  acid  added  and 
then  taken  up  with  water.  The  tungsten  trioxide  remain¬ 
ing  insoluble,  was  filtered  off  and  weighed  as  such. 

Experiment  V. 

3  grams  of  tungsten  trioxide  ....  Voltage,  70-75. 

2  “  “  carbon . Amperage,  120-160. 

Time,  3  minutes. 

The  button  contained  90.39  per  cent  of  tungsten. 
Experiment  VI. 

3  grams  of  tungsten  trioxide  ....  Voltage,  65-80. 

1  gram  of  carbon . Amperage,  75-150. 

Time,  3  minutes. 

The  button  contained  92.54  per  cent  of  tungsten. 
Experiment  VII. 

3  grams  of  tungsten  trioxide  ....  Voltage,  70-90. 

4  “  “  carbon . Amperage,  150-200. 

Time,  6  minutes. 

The  button  obtained  contained  86.60  per  cent  of  tung¬ 
sten. 

Experiment  VIII. 

3  grams  of  tungsten  trioxide  ....  Voltage,  70-80. 

4  “  “  carbon . Amperage,  1 10-175. 

Time,  3  minutes. 

The  button  gave,  upon  analysis,  86.52  per  cent  of  tung¬ 
sten. 

ExpSrime?it  IX. 

3  grams  of  tungsten  trioxide  ....  Voltage,  65-80. 

2  "  “  carbon . Amperage,  100- 170. 

Time,  3^  minutes. 

The  button  contained  89.42  per  cent  of  tungsten. 


6 


Experiment  X. 

3  grams  of  tungsten  trioxide  ....  Voltage,  65-70. 

.5  “  “  carbon . Amperage,  100-125 

Time,  3^  minutes. 

No  metal  was  obtained. 

From  the  above  results  the  amount  of  carbon  used 
appears  to  influence  the  purity  of  the  resulting  metal,  more 
than  variations  in  the  strength  of  the  current  and  time  of 
its  action. 

Attempts  to  prepare  pure  tungsten  failed.  The  metal 
always  contained  carbon,  and  showed  traces  of  unreduced 
oxide.  The  carbon  was  probably  absorbed  from  the  cru¬ 
cible. 

Impure  tungsten  was  prepared  as  above  and  then  placed 
in  a  crucible  lined  with  magnesium  oxide,  to  see  if  it  would 
be  possible  to  burn  off  the  carbon.  Instead  of  the  carbon 
being  burned  out,  the  metal  was  oxidized  to  tungsten 
trioxide  and  the  magnesium  volatilized. 

When  a  crucible,  with  magnesium  oxide  lining,  was 
used  for  the  reduction  of  the  tungsten  trioxide  mixed  with 
carbon,  no  metal  was  obtained. 

Alloys  of  Tungsten  and  Bismuth. 

The  oxide  of  bismuth  used  was  prepared  by  ignition  of 
bismuth  nitrate. 

Experiment  I. 

3  grams  of  tungsten  trioxide  ....  Voltage,  60-70. 

1  gram  of  bismuth  oxide . Amperage,  120- 150. 

4  grams  of  carbon . Time,  2  minutes. 

The  current  was  interrupted  at  the  expiration  of  two 

minutes,  because  the  bismuth  was  being  volatilized.  The 
button  gave  88.00  per  cent  of  tungsten  and  .59  per  cent  of 
bismuth. 


■t 


7 


Method  of  Analysis . 

The  metal  was  oxidized  with  nitric  acid,  evaporated  to 
dryness,  heated  to  about  175  °  C.,  and  then  taken  up  with 
nitric  acid  and  water.  The  tungsten  trioxide  remained 
insoluble  and  was  filtered  off.  In  the  filtrate  the  bismuth 
was  determined  by  precipitating  with  ammonium  carbonate 
in  the  usual  manner. 

Experiment  II. 

2  grams  of  tungsten  trioxide  ....  Voltage,  70-85. 

2  “  “  bismuth  oxide . Amperage,  100-125. 

3  “  “  carbon  . Time,  2  minutes. 

The  metal  gave  upon  analysis  91.63  per  cent  of  tungsten 

and  .64  per  cent  of  bismuth. 

Experiment  III. 

1  gram  of  tungsten  trioxide  ....  Voltage  75-80. 

3  grams  of  bismuth  oxide . Amperage,  75-1 10. 

3  “  “  carbon . Time,  2  minutes. 

The  button  gave  91.12  per  cent  of  tungsten  and  .51  per 
cent  of  bismuth.  Other  experiments  were  tried,  placing 
the  bismuth  oxide  at  the  bottom  of  the  crucible  and  the 
tungsten  trioxide  on  the  top.  By  this  procedure  it  was 
thought  that  the  tungsten  trioxide  would  be  first  reduced, 
and  then  as  the  bismuth  oxide  was  acted  upon  the  bismuth 
would  junite  with  the  tungsten  before  being  volatilized. 
Working  in  this  manner  no  metal  was  obtained  containing 
more  than  a  trace  of  bismuth. 

Tungsten  and  Copper. 


Experiment  /. 

3  grams  of  tungsten  trioxide  ....  Voltage  64-80. 

1  gram  of  copper  oxide . Amperage,  100-160. 

3  grams  of  carbon  ........  Time,  4  minutes. 


8 


The  copper  was  driven  off  and  a  nonhomogeneous  mate¬ 
rial  was  left,  which  showed  traces  of  copper  when  tested 
qualitatively. 

Experiment  II. 

2  grams  of  tungsten  trioxide  ....  Voltage,  78-80. 

2  “  “  copper  oxide . Amperage,  100- 150. 

3  “  “  carbon . Time,  4  minutes. 

Nothing  of  a  metallic  nature  was  obtained. 

Experiment  III. 

1  gram  of  tungsten  trioxide  ....  Voltage,  80-85. 

3  grams  of  copper  oxide . Amperage,  75-100. 

3  “  “  carbon . Time,  4  minutes. 

No  metal  was  obtained. 

In  the  above  experiments  the  oxides  and  the  carbon  were 
intimately  mixed  before  placing  in  the  crucible. 

Experiment  IV. 

In  this  experiment  the  copper  oxide  was  placed  in  the 
bottom  of  the  crucible  and  the  tungsten  trioxide  on  top. 

2  grams  of  tungsten  trioxide  ....  Voltage,  78-80. 

2  “  “  copper  oxide . Amperage,  100-125. 

3  “  “  carbon . Time,  5  minutes. 

After  running  the  above  length  of  time,  cooled  and 

removed  the  button  from  the  furnace.  Portions  of  the 
material  were  not  reduced,  so  reheated  for  a  period  of  three 
minutes ;  at  the  end  of  this  time  a  nonhomogeneous  mass 
was  obtained,  portions  of  which  gave  the  test  for  copper  and 
others  did  not. 

Experiment  V. 

Material  arranged  as  in  Experiment  IV. 

2  grams  of  tungsten  trioxide  ....  Voltage,  60-70. 

2  “  “  copper  oxide . Amperage,  100-150. 

3  “  “  carbon . Time,  5  minutes. 


9 


After  running  for  five  minutes,  the  mixture  was  taken 
from  the  crucible,  mixed  with  more  copper  oxide,  replaced 
in  the  crucible  and  again  treated  with  a  current  of  50  volts 
and  50  amperes.  This  gave  a  copper  colored  button  which 
was  malleable. 

The  button  gave,  upon  analysis,  18.24  Per  cent  °f  tung¬ 
sten,  77.73  per  cent  of  copper  and  3.23  per  cent  of  carbon. 

Method  of  Analysis . 

The  metal  was  oxidized  with  aqua  regia,  evaporated  to 
dryness,  heated  to  1 75 0  C.,  moistened  with  nitric  acid  and 
taken  up  with  water.  The  tungsten  trioxide  was  filtered  off, 
ignited  and  weighed.  In  the  filtrate  the  copper  was  deter¬ 
mined  by  the  electrolytic  process.  The  carbon  was  deter¬ 
mined  by  burning  the  finely  divided  metal  in  oxygen. 

Experiment  VI. 

3  grams  of  tungsten  trioxide  ....  Voltage,  60-80. 

3  “  “  copper  oxide . Amperage,  75-150. 

4  “  “  carbon . Time,  5  minutes. 

After  five  minutes  I  removed  the  assay  from  the  furnace 

and  added  three  grams  of  copper  oxide  and  two  grams  of 
carbon.  Reheated  until  fumes  of  copper  were  noticed  coming 
off  Obtained  a  button  which  had  no  coppery  appearance. 

It  gave,  upon  analysis,  74.86  per  cent  of  tungsten,  18.91 
per  cent  of  copper  and  3.18  per  cent  of  carbon. 

Experiment  VII. 

The  following  experiments  were  made  using  a  crucible 
lined  with  magnesium  oxide  : 

2  grams  of  tungsten  trioxide  ....  Voltage,  60-70. 

4  “  “  copper  oxide . Amperage,  1 25-1 50. 

4  “  “  carbon . Time,  2  minutes. 

The  copper  was  driven  off  and  the  unreduced  tungsten 
trioxide  left  behind. 


IO 


Experiment  VIII. 

2  grams  of  tungsten  trioxide  ....  Voltage,  65-68. 

2  “  “  copper  oxide . Amperage,  1 25-1 30. 

3  “  “  carbon  .  .  6 . Time,  3  minutes. 

No  metal  was  obtained,  the  copper  being  driven  off,  also 

some  of  the  lining  of  the  crucible,  leaving  tungsten  tri¬ 
oxide  behind. 

Experi?nent  IX. 

In  this  experiment,  a  carbon  crucible  was  used  for  the 
first  fusion ;  in  the  refusion  a  crucible  with  a  magnesium 
oxide  lining  was  used. 

2  grams  of  tungsten  trioxide  ....  Voltage,  65. 

3  “  “  copper  oxide . Amperage,  125. 

2  “  “  carbon . Time  of  first  fusion 

3  minutes. 

After  three  minutes  removed  the  brownish  black  material 
from  the  crucible,  mixed  with  two  grams  of  tungsten  tri¬ 
oxide  and  two  grams  of  carbon.  Reheated  until  the  copper 
began  to  volatilize. 

The  fusion  was  slightly  copper  colored,  somewhat  mal¬ 
leable  but  very  granular.  Specific  gravity,  8.39.  Analysis 
gave  79.44  per  cent  of  copper  and  15.48  per  cent  of  tung¬ 
sten.  The  carbon  was  not  determined. 

Tungsten  and  Manganese. 

Experiment  I. 

3  grams  of  tungsten  trioxide  ....  Voltage,  80-85. 

3  “  “  manganese  dioxide  ,  .  .  Amperage,  100- 1 10. 

4  “  “  carbon . Time,  5  minutes. 

A  nonhomogeneous  mass  was  obtained.  Mixed  this 
with  more  carbon  and  reignited  for  three  minutes  with  a  cur¬ 
rent  of  60  volts  and  75  amperes,  using  a  lime  crucible 
for  the  reignition.  The  material  obtained  had  no  metallic 
appearance. 


Experiment  II. 

In  this  experiment  I  used  a  lime  crucible. 

2  grams  of  tungsten  trioxide  ....  Voltage,  60. 

o  o  o  J 

2  “  “  manganese  dioxide  .  .  .  Amperage,  50. 

3  “  “  carbon . Time,  5  minutes. 

Obtained  a  black  porous  mass  which  crumbled  easily  to 

a  black  powder. 


Tungsten  and  Chromium. 

Experiment  I. 

2  grams  of  tungsten  trioxide  ....  Voltage,  72-80. 

2  “  “  chromic  oxide . Amperage,  100- 160. 

2  “  “  carbon . Time,  5  minutes. 

This  experiment  was  run  using  a  lime  crucible.  The 
globule  of  metal  which  was  formed  was  very  hard  and 
brittle,  the  surface  being  covered  with  a  layer  of  chromic 
oxide.  This  globule  was  broken  and  the  interior  portions 
were  found  to  be  of  a  grayish  color,  having  a  specific 
gravity  of  8.96,  and  gave  when  analyzed  2.87  per  cent  of 
chromium  and  97.64  per  cent  of  tungsten. 

Method  of  Analysis. 

The  metal  was  pulverized,  fused  with  sodium  carbonate 
and  potassium  nitrate  and  the  fusion  taken  up  with  water. 
The  tungsten  trioxide  was  thrown  out  of  the  solution  by 
means  of  nitric  acid,  the  solution  evaporated  to  dryness 
and  heated  to  1 75 0  C.  This  residue  was  moistened  with 
nitric  acid,  taken  up  with  water  and  the  tungsten  trioxide 
remaining  insoluble  was  filtered  off,  ignited  and  weighed. 
In  the  filtrate  from  the  tungsten  trioxide  the  chromium  was 
determined  in  the  usual  manner. 

Experiment  II. 

2  grams  of  tungsten  trioxide  ....  Voltage,  72-85. 

2  “  “  carbon . Amperage,  100-150. 

1  gram  of  chromic  oxide . Time,  5  minutes. 


12 


In  the  above  experiment  a  carbon  crucible  was  used.  The 
fusion  had  a  metallic  appearance  in  places.  Replaced  it  in 
the  furnace  and  reheated  for  five  minutes  more,  with  a  cur¬ 
rent  of  80  volts  and  125  amperes.  Obtained  a  black  mass. 

Attempts  to  prepare  alloys,  with  a  large  percentage  of 
chromium  and  a  small  percentage  ot  tungsten,  were  all  un¬ 
successful. 


Tungsten  and  Cobalt. 

Experiment  I 

2  grams  of  tungsten  trioxide  ....  Voltage,  80-85. 

2  “  “  cobaltic  oxide . Amperage,  100-125. 

2  “  “  carbon . Time,  3  minutes. 

A  nonhomogeneous  mass  was  obtained. 

Experiment  II. 

2  grams  of  tungsten  trioxide  ....  Voltage,  70. 

2  “  “  cobaltic  oxide . Amperage,  125. 

1  gram  of  carbon . Time,  3  minutes. 

In  this  experiment  a  lime  crucible  was  used,  but  the  in¬ 
tense  heat  cracked  it  and  the  material  was  lost. 

Experiment  III . 

2  grams  of  tungsten  trioxide  ....  Voltage,  70-80. 

2  “  “  cobaltic  oxide . Amperage,  1 25-1 50. 

I  gram  of  carbon  .........  Time,  I  minute. 

Used  a  lime  crucible  and  obtained  a  button,  which  was 
strongly  magnetic,  very  tough  and  tenacious.  Specific 
gravity  of  10.96. 

Analysis  gave  51.86  per  cent  of  tungsten  and  48.26  per 
cent  of  cobalt. 

Method  of  Analysis. 

Decomposed  with  aqua  regia,  evaporated  to  dryness, 
heated  to  175 0  C.,  took  up  with  nitric  acid  and  water, 


13 


filtered  off  the  tungsten  trioxide,  ignited  and  weighed  it  as 
such.  In  the  filtrate  I  determined  the  cobalt  in  the  usual 
way. 

Experiment  IV 

1  gram  of  tungsten  trioxide  ....  Voltage,  65-70. 

3  grams  of  cobaltic  oxide . Amperage,  1 10-130. 

2  “  “  carbon . Time,  2  minutes. 

Used  a  lime  crucible,  which  was  cracked  during  the 

heating  so  lost  a  portion  of  the  material.  The  metal  that 
was  obtained  was  strongly  magnetic,  very  tough  and  hard 
to  fracture.  The  metal  could  be  easily  filed,  and  had  a 
specific  gravity  of  8.92. 

It  gave  upon  analysis  29.24  per  cent  of  tungsten  and 
70.10  per  cent  of  cobalt. 


Tungsten  and  Nickel. 


Experiment  I. 

1  gram  of  tungsten  trioxide  ....  Voltage,  65-80. 

3  grams  of  nickel  oxide . Amperage,  100-135. 

2  “  “  carbon . Time,  2  minutes. 

I  used  a  lime  crucible  for  the  fusions,  and  obtained  a 
button  that  was  strongly  magnetic,  not  very  hard,  and 
easily  filed.  Specific  gravity  7.31. 

The  analysis  gave  100.65  per  cent  of  nickel  and  no 
tungsten. 

Experiment  II. 

2  grams  of  tungsten  trioxide  ....  Voltage,  68-80. 

2  “  “  nickel  oxide . Amperage,  100-135. 

2  “  “  carbon . Time,  2  minutes. 

This  experiment  was  conducted,  using  a  crucible  lined 
with  magnesium  oxide.  A  globule  was  obtained  that  was 


14 


slightly  magnetic,  could  be  filed  and  was  very  tough.  Its 
specific  gravity  equaled  10.66. 

The  analysis  gave  50.22  per  cent  of  tungsten  and  49.88 
per  cent  of  nickel. 

The  method  of  analysis  was  the  same  as  that  used  with 
the  alloys  of  tungsten  and  cobalt. 

Experiment  III. 

3  grams  of  tungsten  trioxide  ....  Voltage,  75-90. 

2  “  “  carbon . Amperage,  100- 175. 

1  gram  of  nickel  oxide . Time,  1  r/2  minutes. 

In  this  experiment  a  magnesium  oxide  lining  was  used 

in  the  crucible.  The  resulting  button  was  very  hard  and 
nonmagnetic,  extremely  brittle  and  easily  pulverized.  Spe¬ 
cific  gravity  of  12.66. 

The  analysis  gave  91.19  per  cent  of  tungsten  and  8.08 
per  cent  of  nickel. 

Experiment  IV 

4  grams  of  tungsten  trioxide  ....  Voltage,  70-80. 

2  “  “  carbon . Amperage,  75-100. 

1  gram  of  nickel  oxide . Time,  2  minutes. 

The  crucible  used  had  a  magnesium  oxide  lining.  The 
globule  was  dark  colored,  upon  breaking  this  I  found  that 
the  interior  was  a  black  pulverent  mass,  which  contained 
no  metal.  This  was  probably  due  to  an  insufficient  amount 
of  current  being  used. 

Tungsten  and  Tin. 

Experiment  I. 

1  gram  of  tungsten  tri oxide  ....  Voltage,  70. 

3  grams  of  stannic  oxide . Amperage,  100. 

2  “  “  carbon . Time,  1  minute. 

I  used  a  crucible  lined  with  magnesium  oxide.  The  tin 
was  volatilized,  leaving  the  tungsten  in  the  crucible. 


15 


Experiment  II. 

2  grams  of  tungsten  trioxide  ....  Voltage,  68. 

2  “  “  stannic  oxide . Amperage,  75. 

2  “  “  carbon . Time,  1  minute. 


In  this  experiment  I  used  a  crucible  prepared  in  the  same 
way  as  the  one  used  in  Experiment  I.  The  stannic  oxide 
was  placed  in  the  bottom  of  the  crucible  and  the  tungsten 
trioxide  on  top.  At  the  end  of  one  minute  the  crucible 
contained  a  mass  that  resembled  tungsten  trioxide.  The 
current  was  turned  on  again  and  allowed  to  act  for  another 
minute.  A  small  amount  of  yellow  residue  was  obtained 
that  contained  only  tungsten  trioxide. 


Experiment  III. 

3  grams  of  tungsten  trioxide  ....  Voltage,  70. 

2  “  “  carbon . Amperage,  75. 

1  gram  of  stannic  oxide . Time,  2  minutes. 

Used  the  magnesium-lined  crucible,  placing  the  stannic 
oxide  in  the  bottom.  At  the  expiration  of  two  minutes 
there  was  apparently  no  reduction.  Replaced  the  crucible 
in  the  furnace  and  ran  for  three  minutes  longer,  with  a  cur¬ 
rent  of  90  volts  and  75  amperes.  The  material  did  not 
reduce,  so  removed  it,  mixed  with  more  carbon  and  ran  for 
two  minutes  longer.  At  the  conclusion  of  this  run  the 
crucible  contained  only  tungsten  trioxide. 

Experiment  IV. 

5  grams  of  tungsten  trioxide  ....  Voltage,  70. 

5  “  “  stannic  oxide . Amperage,  100. 

5  “  “  carbon . Time,  2  minutes. 

In  this  experiment  I  used  a  graphite  crucible.  No  metal 
was  obtained,  but  a  black,  pulverent  mass  was  left  in  the 
crucible ;  it  was  probably  an  impure  carbide  of  tungsten. 


i6 


From  the  above  results  it  appears  to  be  possible  to  pre-  ' 
pare  alloys  of  tungsten,  starting  from  the  oxides  with  those 
metals  that  require  a  high  temperature  for  their  volatiliza¬ 
tion.  In  the  case  of  those  requiring  a  low  temperature, 
the  oxide  is  apparently  reduced  and  the  metal  driven  off 
before  the  tungstic  oxide  is  reduced.  Doubtless  alloys  of 
tungsten  and  the  lower  fusing  metals  could  be  prepared  by 
starting  with  the  metals  and  melting  them  together ;  but  if 
this  is  attempted  in  the  electric  furnace  the  intense  heat 
drives  off  the  lower  fusing  metal,  leaving  the  one  with  a 
higher  fusing  point  in  the  furnace. 


ALLOYS  OF  MOLYBDENUM. 
Molybdenum  and  Bismuth. 

Experiment  1. 

4  grams  of  molybdenum  trioxide  .  .  .  Voltage,  65-70. 

4  “  “  bismuth  oxide . Amperage,  90-1 20. 

1  gram  of  carbon . Time,  2  minutes. 

The  metal  obtained  was  very  hard.  Specific  gravity 
of  6.81. 

It  gave  upon  analysis  91.61  per  cent  of  molybdenum, 
6.50  per  cent  of  bismuth  and  2.28  per  cent  of  carbon. 

Method  of  Analysis. 

The  alloy  was  decomposed  with  nitric  acid,  the  molyb¬ 
denum  trioxide  filtered  off,  and  the  bismuth  precipitated  in 
the  filtrate  by  means  of  ammonium  carbonate.  The  molyb¬ 
denum  trioxide  was  dissolved  from  off  the  filter  with  ammo¬ 
nium  hydrate,  and  this  solution  united  with  the  filtrate  from 
the  bismuth.  In  the  combined  filtrates  I  determined  the 
molybdenum  by  precipitating  it  with  lead  acetate,  accord- 


7 


in g  to  the  Chatard  method  as  modified  by  Brearly  ( Ch . 


News ,  Vol.  78,  p.  203). 

The  carbon  was  determined  by  burning  the  metal  in 
oxygen. 

Experiment  II. 

2  grams  of  molybdenum  trioxide  .  .  Voltage,  60-70. 

8  “  “  bismuth  oxide . Amperage,  75-1 10. 

1.5  “  “  carbon . Time,  2  minutes. 


After  heating  for  one  and  one-half  minutes  a  granular 
mass  was  obtained.  It  was  re-fused  for  one  minute  in  a 
crucible  lined  with  magnesium  oxide.  The  mass  fused 
together  and  gave  a  very  hard  metallic  button,  with  a  spe¬ 
cific  gravity  of  8.91,  and  upon  analysis  it  gave  92.00  per 
cent  of  molybdenum,  4.81  per  cent  of  bismuth  and  3.90  per 
cent  of  carbon. 


Experiment  III. 

6  grams  of  molybdenum  trioxide  .  .  Voltage,  70-80. 

2  “  “  bismuth  oxide . Amperage,  100-150. 

1  gram  of  carbon . Time,  2  minutes. 


A  crucible  with  magnesium  oxide  lining  was  used  in  this 
experiment.  The  analysis  showed  97.91  percent  of  molyb¬ 
denum,  1. 10  percent  of  bismuth  and  1.2 1  percent  of  carbon. 

Molybdenum  and  Coppell 


Experiment  /. 

2  grams  of  molybdenum  trioxide  .  .  Voltage,  70-85. 

6  “  “  copper  oxide . Amperage,  100-150. 

2  “  “  carbon . Time,  2  minutes. 

I  used  a  carbon  crucible,  placing  the  oxide  of  copper  at 
the  bottom  and  the  molybdenum  trioxide  on  top.  The 
fusion  was  in  two  layers,  the  lower  one  being  copper  and 
the  upper  molybdenum.  Reheated,  hoping  to  bring  the 


i8 


two  in  union ;  the  only  change  brought  about  was  the  vola¬ 
tilization  of  the  copper. 

Experiment  II. 

4  grams  of  molybdenum  trioxide  .  .  Voltage,  65-70. 

4  “  “  copper  oxide . Amperage,  80-100. 

3  “  “  carbon . Time,  2  minutes. 

The  material  was  arranged  in  the  crucible  the  same  as  in 

Experiment  I,  and  a  nonhomogeneous  mixture  was  obtained. 
The  oxides  were  reduced  but  the  metals  did  not  alloy. 

Experiment  III. 

6  grams  of  molybdenum  trioxide  .  ,  Voltage,  60-80. 

2  “  “  copper  oxide . Amperage,  80-125. 

2  “  “  carbon . Time,  1^  minutes. 

The  oxides  and  carbon  were  intimately  mixed  before 
being  put  in  the  crucible,  and  I  obtained  a  porous  mass 
attached  to  the  sides  of  the  crucible.  This  was  removed, 
ground  to  a  powder  and  re-fused  in  a  crucible  lined  with 
magnesium  oxide.  The  lining  absorbed  the  molten  metal. 

Experiment  IV. 

2  grams  of  molybdenum  trioxide  .  .  Voltage,  70-80. 

6  “  “  copper  oxide . Amperage,  100-130. 

2  “  “  carbon . Time,  2  minutes. 

The  oxides  were  reduced  but  the  metals  did  not  alloy. 

Experiment  V. 

4  grams  of  molybdenum  trioxide  .  .  Voltage,  65-75. 

4  “  “  copper  oxide . Amperage,  100-125. 

2  “  “  carbon . .  Time,  2  minutes. 

The  oxides  were  mixed.  The  fusion  gave  a  mixture  of 
the  two  metals  but  no  alloy. 


x9 


Molybdenum  and  Manganese. 

Experiment  I. 

4  grams  of  molybdenum  trioxide  .  .  Voltage,  75-85. 

4  "  “  manganese  dioxide  .  .  .  Amperage,  100-150. 

3  “  “  carbon . Time,  2  minutes. 

A  button,  having  a  specific  gravity  of  7.08  was  obtained. 
Upon  analysis  it  gave  7i.07per  cent  of  molybdenum,  14.36 
per  cent  of  manganese,  9.60  per  cent  of  iron  and  4.34  per 
cent  of  carbon.  The  iron  in  this  alloy  came  from  the  man¬ 
ganese  dioxide. 

Method  of  Analysis. 

The  finely  divided  alloy  was  fused  with  sodium  carbonate 
and  a  little  potassium  nitrate.  Took  up  the  fusion  with 
water,  filtered  off  the  ferric  oxide  and  the  hydrated  oxide  of 
manganese,  dissolved  these  latter  in  hydrochloric  acid  and 
separated  them  by  the  usual  method.  The  filtrate  from  the 
above  oxides  was  treated  with  ammonium  nitrate  and 
evaporated  nearly  to  dryness,  the  manganese  hydrate 
filtered  off,  and  in  the  filtrate  the  molybdenum  determined 
by  precipitating  with  lead  acetate.  The  carbon  was  deter¬ 
mined  by  ignition  in  a  current  of  oxygen. 

Experiment  II. 

2  grams  of  molybdenum  trioxide  .  .  Voltage,  70-80. 

6  u  “  manganese  dioxide  .  .  .  Amperage,  100- 130. 

3  “  “  carbon . Time,  2  minutes. 

The  resulting  alloy  had  the  specific  gravity  6.9. 

Analysis:  60.08  per  cent  of  molybdenum,  21.11  per  cent  of 

manganese,  16.64  Per  cent  °f  iron  and  2.99  per  cent  of  carbon. 

Experiment  III. 

6  grams  of  molybdenum  trioxide  .  .  Voltage,  68-75. 

2  “  “  manganese  dioxide  .  .  .  Amperage,  100- no. 

3  “  “  carbon . Time,  2  minutes. 


20 


The  metal  clung  to  the  sides  of  the  crucible  so  it  could  not 
be  separated  without  removing  graphite  from  the  crucible. 

Molybdenum  and  Chromium. 

Experiment  I. 

5  grams  of  molybdenum  trioxide  .  .  Voltage,  70-85. 

2  “  “  chromic  oxide . Amperage,  75-100. 

2  “  “  carbon  . Time,  4  minutes. 

In  this  experiment  a  carbon  crucible  was  used.  The 
oxide  and  carbon  were  thoroughly  mixed  before  placing  in 
the  crucible.  The  chromic  oxide  melted  and  portions  of  it 
enclosed  some  of  the  molybdic  oxide,  so  the  latter  was  not 
acted  upon. 

Experiment  II. 

5  grams  of  molybdenum  trioxide  .  „  Voltage,  70-85. 

2  “  “  chromic  oxide  .....  Amperage,  75-1 50. 

2  “  “  carbon . Time,  4  minutes. 

In  this  experiment  a  part  of  the  molybdenum  trioxide, 
unmixed  with  carbon,  was  placed  in  the  bottom  of  the  cru¬ 
cible.  On  top  was  placed  a  mixture  of  the  chromic  oxide 
and  the  balance  of  the  molybdenum  trioxide,  mixed  with 
carbon.  This  gave  a  granular  nonhomogeneous  mass. 

Experiment  III. 

2  grams  of  molybdenum  trioxide  .  .  Voltage,  70-90. 

6  “  “  chromic  oxide . Amperage,  100-150. 

2  “  “  carbon . Time,  3  minutes. 

I  used  a  carbon  crucible,  arranging  the  material  as  in  Ex¬ 
periment  II.  This  gave  a  button,  which  was  very  hard  and 
brittle.  Specific  gravity  6.53. 

The  analysis  showed  12.82  per  cent  of  molybdenum, 
76.71  per  cent  chromium,  7.52  per  cent  iron  and  2.55  per 
cent  carbon. 


21 


Method  of  Analysis. 

The  metal  was  fused  with  potassium  bisulphate  and  then 
with  sodium  carbonate  and  potassium  nitrate.  The  fusion 
taken  up  with  water,  and  the  ferric  oxide  filtered  off.  In 
the  filtrate  the  chromium  was  determined  and  in  the  filtrate 
from  this  the  molybdenum  was  precipitated  with  lead  ace¬ 
tate. 

Experiment  IV. 

4  grams  of  molybdenum  trioxide  .  .  Voltage,  70-80. 

4  “  “  chromic  oxide . Amperage,  90-130. 

3  “  “  carbon . Time,  3  minutes. 

Used  a  graphite  crucible  and  obtained  an  alloy  that  was 
very  hard  and  brittle.  Specific  gravity  of  7.65.  Steel  gray 
color.  Analysis  gave  39.96  per  cent  of  molybdenum,  53.24 
per  cent  chromium,  6.22  per  cent  iron  and  a  trace  of  carbon. 

Molybdenum  and  Tin. 

Experiment  I. 

2  grams  of  molybdenum  trioxide  .  .  Voltage,  70-80. 

6  “  “  stannic  oxide . Amperage,  100- 125. 

3  “  “  carbon . Time,  2]/2  minutes. 

No  alloy  was  obtained.  The  tin  was  volatilized,  leaving 

behind  a  mixture  of  molybdenum  and  molybdenum  tri¬ 


oxide. 

Experiment  II. 

4  grams  of  molybdenum  trioxide  .  .  Voltage,  70-85. 

2  “  “  stannic  oxide . Amperage,  80-125. 

3  “  “  carbon . Time,  3  minutes. 

No  metal  was  obtained,  the  tin  being  volatilized. 

Experiment  III. 

6  grams  of  molybdenum  trioxide  .  .  Voltage,  70-90. 

2  “  “  stanni'c  oxide . Amperage,  80-150. 

3  “  “  carbon . Time,  3  minutes. 


22 


In  this  experiment  used  a  crucible  lined  with  magnesium 
oxide,  and  obtained  a  nonhomogeneous  mass,  which  fused 
together  with  the  lining  of  the  crucible. 

Molybdenum  and  Nickel. 


Experiment  I. 

2  grams  of  molybdenum  trioxide  .  .  Voltage,  70-80. 

4  “  “  nickel  oxide . Amperage,  75-125. 

2  “  “  carbon . Time,  2  minutes. 

The  crucible  was  lined  with  magnesium  oxide  for  this 

fusion.  The  metal  obtained  was  very  hard  and  brittle,  non¬ 
magnetic,  and  had  a  specific  gravity  of  7.61.  Upon  analysis 
it  gave  17.72  per  cent  of  molybdenum,  80.93  Per  cen^  °f 
nickel  and  1.63  per  cent  of  carbon. 

Method  of  Analysis. 

The  alloy  was  decomposed  with  nitric  acid  and  the  nickel 
precipitated  with  potassium  hydrate.  In  the  filtrate  the 
molybdenum  was  estimated  with  lead  acetate. 

Experiment  II. 

3  grams  of  molybdenum  trioxide  .  .  Voltage,  80-90. 

3  “  “  nickel  oxide . Amperage,  100- 150. 

2  “  “  carbon . Time,  2  minutes. 

Used  a  crucible  with  magnesium  oxide  lining;  the  lining 
broke  and  the  material  was  lost. 


Experiment  III. 

4  grams  of  molybdenum  trioxide  .  .  Voltage,  75-80. 

2  “  “  nickel  oxide . Amperage,  100- 150. 

2  “  “  carbon . Time,  1  minute. 


The  fusion  was  carried  on  as  in  Experiment  II,  and  gave 
an  alloy  that  was  soft  and  easily  filed.  Nonmagnetic.  Spe¬ 
cific  gravity  of  8.00. 


23 

Analysis:  65.10  per  cent  of  molybdenum  and  3472  per 
cent  of  nickel. 

Experiment  IV 

4  grams  of  molybdenum  trioxide  .  .  Voltage,  80-90. 

2  “  “  nickel  oxide  .  .  ,  .  .  .  Amperage,  75-150. 

2  “  “  carbon . Time,  1  minute. 

A  graphite  crucible  was  used  in  this  experiment  placing 
the  molybdic  oxide  at  the  bottom.  The  metal  was  left  in 
small  globules  clinging  to  the  sides  of  the  crucible.  These 
globules  were  collected  and  refused;  gave  a  black,  porous, 
nonmetallic  mass  of  impure  carbides 


Experiment  V. 

4  grams  of  molybdenum  trioxide  .  .  Voltage,  73-75. 

2  “  “  nickel  oxide . Amperage,  140-160* 

2  “  “  carbon . Time,  1  minute. 


In  this  experiment  a  graphite  crucible  was  used,  the 
material  being  arranged  as  in  the  preceding  experiment. 
The  alloy  was  hard,  brittle  and  nonmagnetic.  Specific 
gravity,  8.88. 

Analysis  :  50.20  per  cent  of  nickel,  42.48  per  cent  of 
molybdenum,  3.05  per  cent  of  carbon  and  4.04  per  cent  of 
silica.  The  silica  probably  came  from  the  material  used  in 
the  manufacture  of  the  graphite  crucible. 

Molybdenum  and  Cobalt. 

Experiment  I, 

2  grams  of  molybdenum  trioxide  ,  .  Voltage,  68-75. 

4  “  “  cobaltic  oxide . Amperage,  100-175. 

2  “  “  carbon . Time,  1  y2  minutes. 

Used  a  crucible  with  magnesium  oxide  lining.  The  alloy 
was  very  hard,  tough  and  magnetic.  Specific  gravity  of 
7-32. 


24 


The  alloy  when  analyzed  gave  17.06  per  cent  of  molyb 
denum  and  82.34  per  cent  of  cobalt. 

Method  of  Analysis. 

The  metal  was  decomposed  with  nitric  acid  and  then 
treated  as  under  the  nickel  and  molybdenum  experiments. 

Experiment  II. 

3  grams  of  molybdenum  trioxide  .  .  Voltage,  70-90. 

3  “  “  cobaltic  oxide . Amperage,  100- 160. 

2  “  “  carbon . Time,  1 y2  minutes. 

Used  a  magnesium  oxide  lining  in  the  crucible,  and  ob¬ 
tained  an  alloy  that  was  very  hard,  tough  and  magnetic. 
Specific  gravity  of  6.44. 

Analysis :  35.64  per  cent  of  molybdenum,  62.91  per  cent 
cobalt  and  1.79  per  cent  carbon. 

Experiment  III. 

3  grams  of  molybdenum  trioxide  .  .  Voltage,  75-80. 

3  “  “  cobaltic  oxide . Amperage,  175- 190. 

2  “  “  carbon  ........  Time,  1  y  minutes. 

In  this  experiment  I  used  a  graphite  crucible,  and  ob¬ 
tained  an  alloy  that  was  hard  and  slightly  magnetic.  Spe¬ 
cific  gravity,  6.94.  The  alloy  was  very  brittle  and  easily 
pulverized. 

Its  analysis  gave  47.10  per  cent  of  molybdenum  and 
52.30  per  cent  of  cobalt. 


Experiment  IV. 

4  grams  of  molybdenum  trioxide  .  .  Voltage,  75-95. 

2  “  “  cobaltic  oxide . Amperage,  1 25-175. 

2  “  “  carbon . Time,  1J/2  minutes. 


The  crucible  was  lined  with  magnesium  oxide.  An  alloy 
was  obtained  that  was  very  hard,  brittle  and  feebly  mag¬ 
netic.  Specific  gravity  of  7.14. 


25 


The  analysis  gave  54.57  per  cent  of  molybdenum  and 
45.35  per  cent  of  cobalt. 

Experiment  V. 

4  grams  of  molybdenum  trioxide  .  .  Voltage,  70-100. 

2  “  “  cobaltic  oxide . Amperage,  1 10-150. 

2  “  “  carbon . Time,  1  *4  minutes. 

Used  a  graphite  crucible,  placing  the  molybdic  oxide  in 
the  bottom.  Gave  an  alloy  that  was  soft  enough  to  be 
filed,  but  was  brittle  and  slightly  magnetic.  Specific 
gravity  of  6.55. 

It  gave  upon  analysis  49.47  per  cent  of  molybdenum  and 
50.86  per  cent  of  cobalt. 

From  these  experiments  it  would  seem  that  cobalt  and 
molybdenum  can  alloy  in  almost  any  proportion. 


REDUCTION  OF  COLUMBIUM  AND  TANTALUM 

OXIDES. 

Reduction  of  Columbium  Oxide. 

Experiment  L 

1  gram  of  columbium  oxide . Voltage,  80. 

2  grams  of  carbon . Amperage,  100. 

Time,  2  minutes. 

The  current  was  allowed  to  act  for  two  minutes,  upon 
allowing  to  cool  there  was  no  indication  of  metal,  so  added 
more  carbon  and  reheated  for  eight  minutes.  A  small 
amount  of  metallic  substance  was  obtained  with  a  specific 
gravity  of  3.43. 

Experiment  II. 

1  gram  of  columbium  oxide  ......  Voltage,  90. 

2  grams  of  carbon . Amperage,  150. 

The  oxide  was  volatilized. 


26 


Experiment  III. 

I  gram  of  columbium  oxide . Voltage,  75. 

carbon . ......  Amperage,  75, 


Time,  15  minutes. 

At  the  expiration  of  fifteen  minutes,  a  grayish  metallic 
substance  was  obtained  having  a  specific  gravity  of  6.61. 
Analysis  of  the  product  gave  88.23  Per  cent  columbium. 

Method  of  Analysis . 

The  metal  was  fused  with  potassium  acid  fluoride,  the 
fusion  dissolved  in  sulphuric  acid,  diluted  with  water  and 
boiled.  The  columbium  came  down  as  oxide,  was  filtered 
off,  ignited  and  weighed  as  the  pentoxide. 

Lack  of  material  prevented  further  experiments  being 
made. 

Reduction  of  Tantalum  Oxide. 

Experiment  I. 

4  grams  of  tantalum  oxide  ....  Voltage,  70-90. 

2  “  “  carbon . .  Amperage,  75-150. 

Time,  2  minutes. 

I  used  a  crucible  lined  with  lime  in  this  experiment,  but 
no  metal  was  obtained,  the  lining  was  melted  and  the  oxide 
volatilized. 

Experiment  II. 

3  grams  of  tantalum  oxide . Voltage,  60-70. 

1^2  “  “  carbon  . Amperage,  75-150. 

Time,  2  minutes. 

In  this  experiment  a  graphite  crucible  was  used,  and  after 
running  for  two  minutes  the  oxide  was  not  reduced.  More 
carbon  was  then  added  and  the  mixture  heated  again  for 
one  minute  with  a  current  of  70-90  volts  and  100-200 
amperes.  Nearly  all  of  the  material  was  driven  off,  and 


27 


only  one  small  globule  of  metal  was  obtained.  This  had  a 
specific  gravity  of  3.18. 

Experiment  III. 

3  grams  of  tantalum  oxide . Voltage,  65-90. 

3  “  “  carbon . Amperage,  75-125. 

Time,  \]/2  minutes. 

A  carbon  crucible  was  used.  After  running  for  one  and 
one-half  minutes,  the  oxide  was  unchanged,  the  carbon 
being  all  burned.  The  oxide  was  again  mixed  with  two 
grams  of  carbon  and  the  whole  moistened  and  pressed 
together  very  firmly.  After  drying  this  mixture  it  remained 
caked  together.  This  caked  material  was  placed  in  the 
crucible  and  heated,  with  a  current  of  64-85  volts  and  75- 
150  amperes,  tor  five  minutes.  No  metal  was  obtained  and 
only  a  very  little  of  the  material  was  left  in  the  crucible. 

Experiment  IV. 

3  grams  of  tantalum  oxide . Voltage,  60-90. 

3  “  “  carbon . Amperage,  75-150. 

Time,  5  minutes. 

No  metal  was  obtained,  while  the  oxide  was  all  volatilized. 
Experiment  V. 

3  grams  of  tantalum  oxide . Voltage,  60-90. 

3  “  "  carbon . Amperage,  70  160. 

Time,  3  minutes. 

The  oxide  and  carbon  were  thoroughly  mixed,  moistened 
and  pressed  together.  After  drying,  the  mixture  was  placed 
in  a  carbon  crucible  and  then  heated.  At  the  expiration  of 
three  minutes  heating  the  current  was  interrupted  and  the 
crucible  allowed  to  cool.  Only  a  small  amount  of  unreduced 
oxide  was  found  in  the  crucible.  From  this  experiment  it 
would  appear  that  the  carbon  is  burned  without  acting  upon 
the  oxide,  and  the  latter  is  simply  volatilized. 


28 


Experiment  VI. 

1.73  grams  of  tantalum  oxide  .  .  .  Voltage,  80-90. 

2  “  “  carbon . Amperage,  100-125. 

Time,  1  minute. 

A  few  small  globules  of  metallic  substance  were  obtained, 
having  a  specific  gravity  of  4.27.  These  gave  upon  an¬ 
alysis  98.92  per  cent  of  tantalum. 

Lack  of  material  prevented  further  investigation  in  this 
direction. 


ACKNOWLEDGMENT. 

This  investigation  was  undertaken  at  the  suggestion  of 
Professor  Edgar  F.  Smith,  and  was  done  under  his  direc¬ 
tion.  I  take  this  opportunity  to  sincerely  thank  him  for 
his  ever  ready  advice,  encouragement  ancfconstant  interest 
throughout  the  work. 


